Liquid detergent dispenser for washing apparatus



March 14, 1961 B. L. BRUCKEN 2,974,832

LIQUID DETERGENT DISPENSER FOR WASHING APPARATUS Filed NOV. 6, 1956 INVENTOR. Byron L. Bracken His Afforney United States Patent 2,974,832 LIQUID DETERGENT DISPENSER FOR WASHING APPARATUS Byron L. Bracken, Dayton, Ohio, assignor to General Motors Corporation, Detroit, Mich., a corporation of Delaware Filed Nov. 6, 1956, Ser. No. 620,633 '3 Claims. (Cl. 222-173) This invention relates to a domestic appliance and more particularly to a detergent dispensing arrangement for washing apparatus.

An object of the invention is to provide a washing apparatus with an electrically operated detergent dispenser that is adapted to dispense detergent into the washing receptacle of the apparatus.

Another object is to provide a dishwasher with an electrically operated pump located on the inner face of the access door of the dishwasher for pumping detergent or the like into the washing receptacle of the dishwasher.

Still another object is to provide a detergent pump for use with washing apparatus including a hot wire mechanism for actuating the pump.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein a preferred form of the present invention is clearly shown.

In the drawings:

Figure l is a front view of a dishwasher that is provided with the detergent dispensing apparatus of this invention;

Figure 2 is a front view of the detergent dispensing mechanism of this invention; and

Figure 3 is a sectional view taken along line 3-3 of Figure 2.

Referring now to Fig. l, a dishwasher generally denoted by reference numeral is provided with a door 12 that closes a front access opening of the dishwasher. The door is pivoted at its lowermost portion and swings from a generally vertically disposed position to a substantially horizontally disposed position. The inner face of the door 12 is provided with a washing agent dispenser having a liquid containing receptacle 14, better shown in Figs. 2 and 3. The receptacle 14 is adapted to contain a liquid washing agent such as a liquid detergent or a wetting agent, and is provided with dispensing means for dispensing the detergent or softener into the dishwasher.

The receptacle 14, as shown in Fig. 3, is suitably secured between the inner and outer panels of the door 12 with the filler cap 16 protruding through the inner panel of the door. The receptacle is provided at its lower end with an outlet opening or conduit 18 that faces toward the washing receptacle of the machine. A check valve 2% is interposed between the interior or receptacle chamber of receptacle 14 and the outlet 18. The check valve includes a flexible diaphragm 22 which carries the stem 24 of the check valve and has openings 26 for the passage of detergent therethrough. The valve 20 normally closes the passages 26 but moves away from the passages 26 when a predetermined pressure is reached in chamber 28 formed in a wall of the receptacle 14, forcing the diaphragm to flex and the valve 20 to move away from the openingsZG. A second check valve 30, identical with valve 20, is interposed between the interior of receptacle 14. The chamber 32 is provided with a flexible diaphragm type of plunger 34 that is preferably made of rubber, neoprene or the like, and which is normally'held in the position shown in Fig. 3 by a spring 36. The lower end of the flexible diaphragm plunger is provided with a metal cap 38 having an integral' button 40 that contactsfa plunger actuating arm 42, as more particularly shown in Fig. 2. It will'be apparent that upon downward movement of diaphragm 34 the check valve 30 is opened whereby the chamber 32 is filled with liquid washing agent flowing from within the interior of receptacle 14. On the up-stroke of diaphragm 34 the liquid washing agent is pushed through a passage 79 and flows past check valve 20 and thence through the outlet 18 into the interior of the dishwasher.

The pump plunger or diaphragm actuating mechanism is more particularly shown in Fig. 2 and includes a main frame member 44 suitably secured to the lower end of receptacle 14. A spring steel member 46 is secured to the main frame member at one end thereof and supports the plunger actuating arm 42. The spring steel member 46 tends to move the plunger actuating arm 42 downwardly in Fig. 2 due to its inherent resilience. The main frame member 44 also supports an electrical contact member 48 and a lower frame member 56. The members 44, 4S and 50 are all connected together by an insulating rivet 52 and are insulated from one another by insulating material 54.

A wire 56, preferably formed of a Nichrome material, is fixed between the lower frame member 50 and the plunger actuating arm 42. The Nichrome wire 56 normally holds the plunger actuating arm 42 in its upper position, that is, in a position wherein the diaphragm is disposed closely adjacent the check valve 30. When the Nichrome wire contracts, the plunger actuating arm 42 is moved upwardly against the bias of spring steel member 46. On the other hand, when the Nichrome wire 56 is heated, such as by the passage of an electric current therethrough, the wire elongates thereby permitting the spring steel member 46 to move the pump actuating arm 4-2 downwardly. When the piunger actuating arm 42 moves downwardly, the spring 36 likewise moves the pump plunger 34 downwardly, and it is seen that the button 40 fixed to pump diaphragm 34 remains in contact with the plunger actuating arm 42.

The spring contact arm 48 of Fig. 2 is provided with an electrical contact 53 that cooperates with an electrical contact 69 secured to a switch contact arm 62 that is in turn secured to pump plungeractuating arm 42. The arm 62 is further provided with a bowed spring member 64 secured to laterally spaced points on the arm 62. With this-arrangement the contacts 53 and 69 are in engagement when the Nichrome wire is not being heated by an electrical current, as shown in Fig. 2.

The electrical contact 48 and the lower frame member 50 are electrically connected with the secondary of a step-down transformer 66, as shown in Fig. 2. The primary of the step-down transformer is. connected with main power lines L and 1. through a timer 68 that is associated with the dishwasher. The timer is adapted to close a circuit to the primary of transformer 66 just before the washing, action begins in the dishwasher, if detergent is to be dispensed, but may be arranged to close a circuit to the primary of transformer 66 just before the final rinsing cycle if. a wetting agent is to be dispensed. When the timer closes a circuit to the primary of transformer 66 a circuit is completed to the Nichrome wire 56 via'the lower frame member 50, the Nichrome wire, the pump actuating arm 42, the metal contact support 62, the contacts 58 and 60, and through the metal contact arm 48 back to the secondary of the transformer. When current passes through the Nichrome wire 56 it elon gates whereupon the inherently resilient orprestressed spring steel member 46 biasingly moves the pump actuating arm downwardly. 'During the downward movement the bowed or over-center spring 64. operatesto move the contact dil upwardlywith a snap action away from the contact 58;" This opens the circuit'tothe Nichromejwire,v

56 and the wirersubsequently contracts to again move the pump-'actuatingarm fl upwardly. During the contrac- Patented Mar. 14, 1961' said wire to periodically heat the same. 7

tion of Nichrome wire 56 and upward movement of pump actuating arm 42, the bowed or over-center spring member 64 snaps back to again close the contacts 58 and 60. This elongation and contraction of Nichrome wire 56 opens and closes the contacts 58 and 60 due to the snap action of the over-center spring 64. The elongation and contraction of the Nichrome wire also moves pump diaphragm arm 42 upwardly and downwardly in order to reciprocate the diaphragm 34.

In operation, the door 12 of the dishwasher is opened and the filler cap 16 of receptacle 14 removed in order to fill the receptacle with a liquid washing agent. The door is then closed and the timer set into operation. At

- some predetermined point during the operation of the timer a circuit is closed to the primary of transformer 66 and in turn, a circuit closed to the Nichrome wire 56. The heating of they Nichrome wire and the opening and closing of contacts 58 and 60 produces a reciprocation of diaphragm 34. The diaphragm 34 will be reciprocated as long as the timer completes a circuit to the primary of transformer 66 and the period of time that the primary is energized may be so calculated as to pump a predetermined amount of washing agent into the interior of the dishwasher. The timer thus initiates operation of the detergent pump at some predetermined point in the dishwashing cycle and also predetermines the length of time that the pump operates.

Although the detergent dispensing arrangement of this invention has been disclosed with a dishwasher having a front access opening, it will be apparent to those skilled in the art that the detergent pump is equally applicable to a clothes washing machine or to any other sort of washing apparatus. a a

While the form of embodiment of the invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted, as may come within the scope of the claims which follow.

What is claimed is as follows:

1. A liquid detergent dispenser comprising, a receptacle 7 ing chamber, a second check valve in said outlet passage,

a diaphragm actuator abutting said flexible diaphragm for reciprocating the same, resilient means for moving said actuator in one direction, a single, straight metal wire a connected between a fixed point and said actuator for holding said actuator against movement by said resilient means, said wire elongating upon heating-to permit'said resilient means to move said actuator to charge said dispensing chamber with liquid detergent from said storage chamber and contractingupon cooling to move said actu ator ,a gainst the bias of said resilient means to'pump said liquid detergent from said dispensing chamber, and circuit means including a switch actuated by said wire for periodically passing an electrical current through V '2. A pumpfor pumping liquid detergent or the lik into a compartment and adapted formounting within a side wall of said compartment comprising, a chamber,

i plunger means in one direction, said wire elongating 7 upon the passage of an electrical current therethrough and shortening upon the cessation of said; electrical current, and means for repeatedly interrupting said current.

' 3.,In combination witha washing apparatus, a substantially vertically .disposeddoor having an inner face andjadapted to move between'a vertical closed position and a horiz'ontal open position, a liquid washing agent dispenser secured to said inner face fof' said door. andhaving a receptacle chamber and a pumping chamber, said receptacle chamber having a closable filler opening extending through said inner face for filling said receptacle chamber with a supply of washing agent when said door is in an open position, said pumping chamber having an outlet conduit extending through said inner face for conveying washing agent to said washing apparatus, a partition separating said chambers and having a passge interconnecting said chambers, a first check valve in said outlet conduit and movable to open said pumping chamber to said washing apparatus in response to the pressure in said pumping chamber, a second check valve in said passage and movable to interconnect said chambers in washing agent flow relationship in response to the pressure in said pumping chamber, said pumping chamber having a flexible diaphragm in one wall thereof opposite said partition, a coil spring having one end abutting said. partition and its other end biasing said diaphragm outwardly from said pumping chamber for creating a negative pressure in said pumping chamber, a metal diaphragm cap on the side of said diaphragm remote from said pumping chamber, and a diaphragm actuating machanism for creating a positive pressure in said pumping chamber, said actuating mechanism including a main frame member secured to said dispenser adjacent said pumping chamber and having first and second end portions disposed on opposite sides of said diaphragm cap, a spring member joined to said second end portion, a diaphragm actuating arm secured to said' spring member and extending into engagement with said diaphragm cap, said spring member adapted to 'bias said actuating'arm in a direction away from said diaphragm cap in order to render effective said coil spring, a fixed electrical contact insulatingly connected tosaid first end portion of said main frame, a lower frame member insulatingly connected to said fixed electrical contact, a switch arm joined to said diaphragm actuating arm and extending into selective engaging and disengaging relationship with said fixed electrical contact, an over-center spring member connected to said actuating arm for imparting snap action to the engaging and disengaging movement of said actuating arm relative to said fixed electrical contact, a straight wire afiixed at one end to said lower frame member and at the other end thereof to said actuating arm between the jointure of said actuating arm and said switch arm and the jointure of said spring member and said second end portion of said main frame member, circuit means connected to said lower frame member and said fixed contact member selectively to place said lower frame member, said wire, said actuating arm, said switch arm, and said'fixed contact in series electrical .flow relationship, and means including 'a timer for energizing said circuitmeans to elongate said wire and render efiective said spring member to move said actuating arm in a'direction away from said diaphragm cap, whereby said coil spring and said diaphragm cooperate to create a negative pressure in said pumping chamber to draw washing agent into said pumping chamber, and for deenergizing said circuit means, whereby said wire contracts to pump said washing agent from'said pumping'chamber.

7 References Cited in the file of this patent UNITED STATES PATENTS V V V 

